Logic program-based updates

Abstract

In logic program-based updates, contradictory information elimination, conflict resolution, and syntactic representation are three major issues that interfere with each other and significantly influence the update result. We observe that existing approaches of logic program-based updates, in one way or another, are problematic to deal with these issues. In this article, we address all these problems in a systematic manner. Our approach to the logic program-based update has the following features: (1) a prioritized logic programming language is employed for providing a formal basis of formalizing logic program-based updates, so that information conflict and its related problems in updates can be handled properly; (2) our approach presents both semantic characterization and syntactic representation for the underlying update procedure, and hence is consistent with the nature of updates within the logic program extent-declarative semantics and syntactic sensitivity; and (3) our approach also provides nontrivial solutions to simplify various update evaluation procedures under certain conditions.